Electrocardiographic mapping (ECM) is a technology that is used to determine and display heart electrical information from sensed electrical signals. Mapping of cardiac electrical activity can be important in the diagnosis of cardiac arrhythmia such as fibrillation, including atrial and ventricular fibrillation, as well as tachycardia, including atria tachycardia and ventricular tachycardia. In many arrhythmias, the origin of the aberrant beat is from a small region of abnormal or triggered activity that propagates from this point and results in abnormal activation of the heart. Detecting and visualizing this mechanism of arrhythmias can be relevant to the clinical diagnosis of arrhythmias.